1. Field of the Invention
The present invention relates generally to mattress assemblies and, more particularly, to new and improved mattress assemblies of the type including a pillow top construction formed in a manner to provide long lasting, resilient comfort for users of the mattress.
2. Description of the Related Art
The quality of a mattress user's sleep and the rest derived from such sleep are dependent upon the comfort of the individual lying on a sleeping surface. Accordingly, attempts to improve the comfort of mattresses have been ongoing over an extended period of time. An ideal mattress, or sleep surface, would essentially eliminate all discomfort caused by excessive pressure on the individual or improper support. Thus, one form of mattress that has become popular is of a type comprising a mattress core, which may have an innerspring construction therein together with what is known as a pillow top arrangement.
Heretofore, pillow tops for use in mattress constructions have been formed by inserting soft resilient filling materials into a sleeve or enclosure which is interconnected with a top surface of a mattress core. Normally, when an innerspring coil mattress core is employed, the pillow top construction serves to essentially cushion the innerspring coils and to allow for more independent and unrestrained articulation resulting in improved conformability and interface pressure, thus improving overall comfort levels for a user of the mattress. An example of a pillow top mattress is disclosed in U.S. Pat. No. 4,955,095 (the '095 patent). There, it is taught to use a removable or detachable pillow top which can be removed from a mattress innerspring core for cleaning. The filling material for the pillow top is disclosed as being hollow fill fibers or polyurethane foam. Alternatively, a piece of flexible resilient convoluted polyurethane foam is taught for inclusion in the pillow top construction of the '095 patent.
In other known pillow top mattress assemblies, the filling materials enclosed within the pillow top sleeve or envelope have consisted of other textile or polymeric based products, such as resin treated textile clipping pads, polyurethane foam (slab or pin cored), and/or polymeric fiber pads (e.g., polyester, polypropylene and like flexible, resilient polymeric compositions).
A significant disadvantage of these known pillow top constructions, is that the filling materials which have been employed in prior pillow tops generally will lose approximately 25% of their original thickness during the normal life of a mattress. Thus, the original comfort provided by known pillow tops diminishes with time and use as a result of the loss of resilience of the filling material.
Accordingly, it is a primary object of the present invention to provide a pillow top mattress construction in which the pillow top retains its original thickness and resilience over an extended period of time so as to remain comfortable over the full life of the mattress.
A further object of this invention is to provide pillow top constructions which can be manufactured readily by efficient, conventional methods.
A still further object is to provide a pillow top construction which is cost-effective to manufacture and will not add appreciably to the ultimate price of the mattress.